diff -Naur wmbiff-0.4.35.orig/wmbiff/wmbiff.c wmbiff-0.4.35/wmbiff/wmbiff.c
--- wmbiff-0.4.35.orig/wmbiff/wmbiff.c	2019-07-23 15:58:58.000000000 +0200
+++ wmbiff-0.4.35/wmbiff/wmbiff.c	2020-03-08 12:25:32.766264038 +0100
@@ -104,6 +104,8 @@
 
 Cursor busy_cursor, ready_cursor;
 
+Display *display;
+
 static __inline /*@out@ */ void *
 malloc_ordie(size_t len)
 {
diff -Naur wmbiff-0.4.35.orig/wmgeneral/wmgeneral.h wmbiff-0.4.35/wmgeneral/wmgeneral.h
--- wmbiff-0.4.35.orig/wmgeneral/wmgeneral.h	2019-07-23 15:57:57.000000000 +0200
+++ wmbiff-0.4.35/wmgeneral/wmgeneral.h	2020-03-08 12:25:16.223256712 +0100
@@ -36,7 +36,7 @@
  /* Global variable */
 /*******************/
 
-Display *display;
+extern Display *display;
 
   /***********************/
  /* Function Prototypes */